Minimum surface clamp



y 9, 1967 L. c. FI KLE 3,317,973

MINIMUM S URFACE CLAMP Filed May 21, 1965 A TTCE/VE Y United States Patent OfiFice 3,317,973 Patented May 9, 1967 3,317,973 MINIMUM SURFACE CLAMP Lewis C. Finkle, 6260 N. Loma Ave., Temple City, Calif. 91780 Filed May 21, 1965, Ser. No. 457,737 2 Claims. (Cl. 24-252) This invention relates to a minimum surface clamp and more particularly to a clamp for supporting material with a minimum amount of contact area during painting of the material.

Present types of clamps used for holding materials to be painted have contact areas which shield large portions of the material from the paint. It is then necessary to materially retouch the materials after the original paint application. Such retouching is time consuming and does not always result in the most attractive overall appearance of the material. The present invention provides a clamp for supporting an article while being painted at four points of contact with a minimum amount of contact area at each point so that only slight retouching of the article need to be done after the original paint has been applied. The clamp comprises two legs which are held together by a pair of U-shaped spring members so that one end of the legs provides the gripping portion for opening the clamp. The other end of each leg has two contact fingers which are staggered transversely of the leg and longitudinally of the leg so as to provide the four-point contact without any of the fingers being opposite one another. By having a (minimum contact for each finger, it is possible to quickly touch up the four points of contact and in many cases, the small areas of contact are not noticeable so that retouching is not necessary.

It is therefore an object of the present invention to provide a minimum surface clamp for gripping and holding material with a minimum of gripping area while the material is being painted.

Another object of the invention is to provide a minimum surface clamp which comprises a pair of legs on which are staggered fingers in locations to permit staggered contact points on the material.

Another object of the invention is to provide a minimum surface clamp in which the legs are connected together by means of a spring so that gripping fingers on the legs will engage and hold an article.

These and other objects of the invention not specifically set forth above will become readily apparent from the accompanying description and drawings in which:

FIGURE 1 is a side elevational view of the minimum surface clamp of the present invention showing the two legs connected together by springs;

FIGURE 2 is a top plan view along line 2.2 of FIGURE 1 illustrating the manner in which the contact fingers are staggered; and

FIGURE 3 is a perspective view showing the clamp supporting a piece of sheet material by the four staggered fingers.

Referring to the embodiment of the invention chosen for purposes of illustration, the minimum surface clamp comprises legs 11 and 12 which are normally held together at an angle to each other by means of the curved leaf springs 13 and 14. Rivets 15 connect leg 11 with one end of the springs while rivets 16 connect leg 12 with the other end of the springs. The ends 11a and 12a of arms 11 and 12, respectively, contain openings 18 and 19, respectively, one or both of which can receive a conveyor support wire 20 to carry the clamp along a conveyor in a paint booth.

The other end [11b of arm 11 carries two fingers 22 and 23 which project inwardly at an angle to the arm and terminate at edges 22a and 23b, respectively. The fingers 22 and 23 are staggered since finger '22 is on one side of the arm 11 and the finger 23 is on the other side. Also, finger 23 is located inwardly from finger 22. In a similar manner, the end 12b of the arm 12 carries two contact fingers 24 and 25 which terminate in the sharp edges 24a and 25a. The fingers 24 and 25 are located on opposite sides of leg 12 so as to be opposite to the fingers 22 and 23, respectively, on arm 11, Therefore, each finger will contact a different part of material clamped between the fingers. The fingers on each leg are formed by cutting an irregular notch in the end of the leg and then bending the ends of the notch inwardly.

In FIGURE 1, the clamp is shown in the unsprung condition in which the fingers on one leg project past the fingers on the other leg and there is no stress on the springs 13 and '14. In FIGURE 3, the clamp is applied to a sheet of material and the fingers are so proportioned that each finger will engage the surface of the plate along the sharp edge of the finger. In this condition, the springs are stressed in order to hold the fingers against the surface of the plate 25 to provide a four-point suspension of the plate. Each finger engages the plate at a different location because the points are staggered and with the illustrated finger configuration, four-point contact is obtained on plates ranging from .003 inch to .050 inch. By utilizing a V-shaped cutout to form the fingers, a minimum area of the ends 11b and 12b shield the edge of the plate at the clamp and the fingers hold the ends of the arms away from the surfaces of the plate so that paint can be sprayed underneath the arms and obtain substantially full coverage of the plate surfaces under the arms of the clamp. After the painting has been completed and the clamp removed, the amount of unpainted area is so small that in some cases retouching is not required whereas in other cases, the unpainted area can be slightly touched up to provide full paint coverage for the area where the clamp was located. It is understood that the type of clamp spring can be varied and the length and locations of the individual legs to obtain finger contact will be determined by the article thickness range over which the clamp is to be utilized. Various other modifications are contemplated by those skilled in the art without departing from the spirit and scope of the invention as hereinafter defined by the appended claims.

What is claimed is:

-1. A minimum surface clamp comprising first and second legs; spring means having one end secured to the inner surface of each of said first and second legs to normally hold said legs at an angle to one another; the ends of said legs farthest apart serving as finger grips for opening the clamp against the force of said spring means; and staggered finger means projecting inwardly from the other ends of said legs nearest together to engage and support a piece of material placed between the fingers after the clamp is opened, said staggered finger means comprising only two fingers projecting from each leg at opposite sides thereof and at locations separated along the length of the leg, the pair of fingers on one leg being staggered with respect to the fingers on the other leg.

2. A minimum surface clamp as defined in claim 1 wherein said fingers are formed at the ends of V-notches cut in said legs so that the near ends of the legs are 3 4 spaced from said material and overlap a minimum sur- 2,810,177 10/1957 Hutchison 24-259 face areaof said material. 1 3,047,197 7/1962 Singer 22396 References Cited by the Examiner FOREIGN PATENTS UNITED STATES PATENTS 5 549,985 12/ 1922 France. 2,094,107 9/1937 Post 24-259 WILLIAM FELDMAN, Primary Examiner.

2,506,839 5/1950 Mead- DONALD A. GRIFFIN, Examiner. 

1. A MINIMUM SURFACE CLAMP COMPRISING FIRST AND SECOND LEGS; SPRING MEANS HAVING ONE END SECURED TO THE INNER SURFACE OF EACH OF SAID FIRST AND SECOND LEGS TO NORMALLY HOLD SAID LEGS AT AN ANGLE TO ONE ANOTHER; THE ENDS OF SAID LEGS FARTHEST APART SERVING AS FINGER GRIPS FOR OPENING THE CLAMP AGAINST THE FORCE OF SAID SPRING MEANS; AND STAGGERED FINGER MEANS PROJECTING INWARDLY FROM THE OTHER ENDS OF SAID LEGS NEAREST TOGETHER TO ENGAGE AND SUPPORT A PIECE OF MATERIAL PLACED BETWEEN THE FINGERS AFTER THE CLAMP IS OPENED, SAID STAGGERED FINGER MEANS COMPRISING ONLY TWO FINGERS PROJECTING FROM EACH LEG AT OPPOSITE SIDES THEREOF AND AT LOCATIONS SEPARATED ALONG THE LENGTH OF THE LEG, THE PAIR OF FINGERS ON ONE LEG BEING STAGGERED WITH RESPECT TO THE FINGERS ON THE OTHER LEG. 